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Van HT, Harkins PR, Patel A, Jain AK, Lu Y, Bedford MT, Santos MA. Methyl-lysine readers PHF20 and PHF20L1 define two distinct gene expression-regulating NSL complexes. J Biol Chem 2022; 298:101588. [PMID: 35033534 PMCID: PMC8867114 DOI: 10.1016/j.jbc.2022.101588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 01/06/2022] [Accepted: 01/08/2022] [Indexed: 11/16/2022] Open
Abstract
The methyl-lysine readers plant homeodomain finger protein 20 (PHF20) and its homolog PHF20-like protein 1 (PHF20L1) are known components of the nonspecific lethal (NSL) complex that regulates gene expression through its histone acetyltransferase activity. In the current model, both PHF homologs coexist in the same NSL complex, although this was not formally tested; nor have the functions of PHF20 and PHF20L1 regarding NSL complex integrity and transcriptional regulation been investigated. Here, we perform an in-depth biochemical and functional characterization of PHF20 and PHF20L1 in the context of the NSL complex. Using mass spectrometry, genome-wide chromatin analysis, and protein-domain mapping, we identify the existence of two distinct NSL complexes that exclusively contain either PHF20 or PHF20L1. We show that the C-terminal domains of PHF20 and PHF20L1 are essential for complex formation with NSL, and the Tudor 2 domains are required for chromatin binding. The genome-wide chromatin landscape of PHF20–PHF20L1 shows that these proteins bind mostly to the same genomic regions, at promoters of highly expressed/housekeeping genes. Yet, deletion of PHF20 and PHF20L1 does not abrogate gene expression or impact the recruitment of the NSL complex to those target gene promoters, suggesting the existence of an alternative mechanism that compensates for the transcription of genes whose sustained expression is important for critical cellular functions. This work shifts the current paradigm and lays the foundation for studies on the differential roles of PHF20 and PHF20L1 in regulating NSL complex activity in physiological and diseases states.
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Affiliation(s)
- Hieu T Van
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; Center for Cancer Epigenetics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; Graduate Program in Genetics & Epigenetics, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, Texas, USA
| | - Peter R Harkins
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Avni Patel
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Abhinav K Jain
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; Center for Cancer Epigenetics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Yue Lu
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; Center for Cancer Epigenetics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Mark T Bedford
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; Center for Cancer Epigenetics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Margarida A Santos
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; Center for Cancer Epigenetics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
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Coleman N, Moyers JT, Harbery A, Vivanco I, Yap TA. Clinical Development of AKT Inhibitors and Associated Predictive Biomarkers to Guide Patient Treatment in Cancer Medicine. Pharmgenomics Pers Med 2021; 14:1517-1535. [PMID: 34858045 PMCID: PMC8630372 DOI: 10.2147/pgpm.s305068] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 11/03/2021] [Indexed: 11/29/2022] Open
Abstract
The serine/threonine kinase AKT is a critical effector of the phosphoinositide 3-kinase (PI3K) signaling cascade and has a pivotal role in cell growth, proliferation, survival, and metabolism. AKT is one of the most commonly activated pathways in human cancer and dysregulation of AKT-dependent pathways is associated with the development and maintenance of a range of solid tumors. There are multiple small-molecule inhibitors targeting different components of the PI3K/AKT pathway currently at various stages of clinical development, in addition to new combination strategies aiming to boost the therapeutic efficacy of these drugs. Correlative and translational studies have been undertaken in the context of clinical trials investigating AKT inhibitors, however the identification of predictive biomarkers of response and resistance to AKT inhibition remains an unmet need. In this review, we discuss the biological function and activation of AKT, discuss its contribution to tumor development and progression, and review the efficacy and toxicity data from clinical trials, including both AKT inhibitor monotherapy and combination strategies with other agents. We also discuss the promise and challenges associated with the development of AKT inhibitors and associated predictive biomarkers of response and resistance.
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Affiliation(s)
- Niamh Coleman
- Department of Investigational Cancer Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Justin T Moyers
- Department of Investigational Cancer Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Division of Hematology and Oncology, Department of Medicine, University of California, Irvine, Orange, CA, USA
| | - Alice Harbery
- Division of Cancer Therapeutics, Institute of Cancer Research, London, SM2 5NG, UK
| | - Igor Vivanco
- Institute of Pharmaceutical Sciences, School of Cancer and Pharmaceutical Sciences, King’s College London, London, UK
| | - Timothy A Yap
- Department of Investigational Cancer Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Institute for Applied Cancer Science, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Khalifa Institute for Personalized Cancer Therapy, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
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Neamati D, Khedri A, Aberomand M, Hemmati AA, Mohammadzadeh M, Akbari Baghbani K, Mohammadzadeh G. Metformin synergistically increases the anticancer effects of lapatinib through induction of apoptosis and modulation of Akt/AMPK pathway in SK-BR3 breast cancer cell line. IRANIAN JOURNAL OF BASIC MEDICAL SCIENCES 2021; 24:1529-1537. [PMID: 35317106 PMCID: PMC8917838 DOI: 10.22038/ijbms.2021.58825.13069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 10/18/2021] [Indexed: 11/06/2022]
Abstract
Objectives Combination chemotherapy is a beneficial intervention for breast cancer, versus single therapy. We investigated the effect of Metformin (Met) on Lapatinib (Lap)-induced apoptosis in SK-BR3 cells. Materials and Methods Toxic effect of Met and Lap on SK-BR3 cells was measured using MTT assay. Flow cytometry was used to measure the co-treatment effect of Met on lapatinib-induced apoptosis. The relative expression of Bax, Bcl2, and P21 was measured using a real-time PCR. The activity of caspase 3 and 9 was measured using an ELISA kit. The protein level of AMPK and Akt was determined using Western blot analysis. Results Metformin and lapatinib alone and combined form showed significant time- and dose-dependent toxic effects on SK-BR3 cell viability. The greatest synergistic inhibitory effect on the cell viability [combination index (CI) = 0.51] was remarkable at Met 100 mM combined with Lap 100 nM. The combination has a stronger apoptotic death (46%) versus lapatinib alone. The combination considerably increased the mRNA expression of Bax and P21, and caspase 3 and 9 activity, while, decreasing the mRNA expression of Bcl2. Additionally, the combination significantly up-regulated and down-regulated the protein levels of AMPK and Akt, respectively. Conclusion The metformin-lapatinib combination can induce more potent apoptotic death versus each compound individually. The combination may be suggested as a valuable therapeutic intervention in patients with breast cancer. However, additional in vivo studies are necessary to evaluate the clinical use of the combination for induction of apoptosis and its antitumor effects.
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Affiliation(s)
- Davood Neamati
- Department of Clinical Biochemistry, School of Medicine, Ahvaz Jundishapur University of Medical Sciences,Ahvaz, Iran
| | - Azam Khedri
- Department of Clinical Biochemistry, School of Medicine, Ahvaz Jundishapur University of Medical Sciences,Ahvaz, Iran
| | - Mohammad Aberomand
- Toxicology Research Center, Department of Clinical Biochemistry, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Ali-Asghar Hemmati
- Medicinal Plant Research Center, Department of Toxicology, School of Pharmacy, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Maryam Mohammadzadeh
- Translational Ophthalmology Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | | | - Ghorban Mohammadzadeh
- Hyperlipidemia Research Center, Department of Clinical Biochemistry, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran,Corresponding author: Ghorban Mohammadzadeh. Hyperlipidemia Research Center, Department of Clinical Biochemistry, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran. Tel: +98-0911-3436812; Fax: +98-611-3332036; Email :
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Lieberknecht V, Engel D, Rodrigues ALS, Gabilan NH. Neuroprotective effects of mirtazapine and imipramine and their effect in pro- and anti-apoptotic gene expression in human neuroblastoma cells. Pharmacol Rep 2020; 72:563-570. [DOI: 10.1007/s43440-019-00009-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 07/19/2019] [Accepted: 08/25/2019] [Indexed: 12/13/2022]
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Shariati M, Meric-Bernstam F. Targeting AKT for cancer therapy. Expert Opin Investig Drugs 2019; 28:977-988. [PMID: 31594388 PMCID: PMC6901085 DOI: 10.1080/13543784.2019.1676726] [Citation(s) in RCA: 145] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 10/02/2019] [Indexed: 12/17/2022]
Abstract
Introduction: Targeted therapies in cancer aim to inhibit specific molecular targets responsible for enhanced tumor growth. AKT/PKB (protein kinase B) is a serine threonine kinase involved in several critical cellular pathways, including survival, proliferation, invasion, apoptosis, and angiogenesis. Although phosphatidylinositol-3 kinase (PI3K) is the key regulator of AKT activation, numerous stimuli and kinases initiate pro-proliferative AKT signaling which results in the activation of AKT pathway to drive cellular growth and survival. Activating mutations and amplification of components of the AKT pathway are implicated in the pathogenesis of many cancers including breast and ovarian. Given its importance, AKT, it has been validated as a promising therapeutic target.Areas covered: This article summarizes AKT's biological function and different classes of AKT inhibitors as anticancer agents. We also explore the efficacy of AKT inhibitors as monotherapies and in combination with cytotoxic and other targeted therapies.Expert opinion: The complex mechanism following AKT inhibition requires the addition of other therapies to prevent resistance and improve clinical response. Further studies are necessary to determine additional rational combinations that can enhance efficacy of AKT inhibitors, potentially by targeting compensatory mechanisms, and/or enhancing apoptosis. The identification of biomarkers of response is essential for the development of successful therapeutics.
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Affiliation(s)
- Maryam Shariati
- Department of Investigational Cancer Therapeutics, Division of Cancer Medicine, UT MD Anderson Cancer Center, Houston, TX, USA
| | - Funda Meric-Bernstam
- Department of Investigational Cancer Therapeutics, Division of Cancer Medicine, UT MD Anderson Cancer Center, Houston, TX, USA
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6
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Hwang I, Cho SW, Ahn JY. Chaperone-E3 Ligase Complex HSP70-CHIP Mediates Ubiquitination of Ribosomal Protein S3. Int J Mol Sci 2018; 19:ijms19092723. [PMID: 30213050 PMCID: PMC6163665 DOI: 10.3390/ijms19092723] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Revised: 09/07/2018] [Accepted: 09/10/2018] [Indexed: 12/15/2022] Open
Abstract
In addition to its role in ribosome biogenesis, ribosomal protein S3 (RPS3), a component of the 40S ribosomal subunit, has been suggested to possess several extraribosomal functions, including an apoptotic function. In this study, we demonstrated that in the mouse brain, the protein levels of RPS3 were altered by the degree of nutritional starvation and correlated with neuronal apoptosis. After endurable short-term starvation, the apoptotic function of RPS3 was suppressed by Akt activation and Akt-mediated T70 phosphorylation, whereas after prolonged starvation, the protein levels of RPS3 notably increased, and abundant neuronal death occurred. These events coincided with ubiquitination and subsequent degradation of RPS3, controlled by HSP70 and the cochaperone E3 ligase: carboxy terminus of heat shock protein 70-interacting protein (CHIP). Thus, our study points to an extraribosomal role of RPS3 in balancing neuronal survival or death depending on the degree of starvation through CHIP-mediated polyubiquitination and degradation.
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Affiliation(s)
- Inwoo Hwang
- Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, Suwon 16419, Korea.
- Single Cell Network Research Center, Sungkyunkwan University School of Medicine, Suwon 16419, Korea.
| | - Sung-Woo Cho
- Department of Biochemistry and Molecular Biology, University of Ulsan, College of Medicine, Seoul 05505, Korea.
| | - Jee-Yin Ahn
- Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, Suwon 16419, Korea.
- Single Cell Network Research Center, Sungkyunkwan University School of Medicine, Suwon 16419, Korea.
- Samsung Biomedical Research Institute, Samsung Medical Center, Seoul 06351, Korea.
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Hughes DC, Ellefsen S, Baar K. Adaptations to Endurance and Strength Training. Cold Spring Harb Perspect Med 2018; 8:cshperspect.a029769. [PMID: 28490537 DOI: 10.1101/cshperspect.a029769] [Citation(s) in RCA: 159] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The capacity for human exercise performance can be enhanced with prolonged exercise training, whether it is endurance- or strength-based. The ability to adapt through exercise training allows individuals to perform at the height of their sporting event and/or maintain peak physical condition throughout the life span. Our continued drive to understand how to prescribe exercise to maximize health and/or performance outcomes means that our knowledge of the adaptations that occur as a result of exercise continues to evolve. This review will focus on current and new insights into endurance and strength-training adaptations and will highlight important questions that remain as far as how we adapt to training.
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Affiliation(s)
- David C Hughes
- Department of Neurobiology, Physiology and Behavior, Functional Molecular Biology Laboratory, University of California Davis, Davis, California 95616
| | - Stian Ellefsen
- Section of Sports Sciences, Lillehammer University College, 2604 Lillehammer, Norway.,Innlandet Hospital Trust, 2380 Brumunddal, Norway
| | - Keith Baar
- Department of Neurobiology, Physiology and Behavior, Functional Molecular Biology Laboratory, University of California Davis, Davis, California 95616
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Smiles WJ, Camera DM. The guardian of the genome p53 regulates exercise-induced mitochondrial plasticity beyond organelle biogenesis. Acta Physiol (Oxf) 2018; 222. [PMID: 29178461 DOI: 10.1111/apha.13004] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 10/31/2017] [Accepted: 11/22/2017] [Indexed: 12/28/2022]
Abstract
The Guardian of the Genome p53 has been established as a potent tumour suppressor. However, culminating from seminal findings in rodents more than a decade ago, several studies have demonstrated that p53 is required to maintain basal mitochondrial function [ie, respiration and reactive oxygen species (ROS) homeostasis]. Specifically, via its role(s) as a tumour suppressor, p53 intimately surveys cellular DNA damage, in particular mitochondrial DNA (mtDNA), to ensure that the mitochondrial network is carefully monitored and cell viability is upheld, because aberrant mtDNA damage leads to apoptosis and widespread cellular perturbations. Indeed, data from rodents and humans have demonstrated that p53 forms an integral component of the exercise-induced signal transduction network regulating skeletal muscle mitochondrial remodelling. In response to exercise-induced disruptions to cellular homeostasis that have the potential to harm mtDNA (eg, contraction-stimulated ROS emissions), appropriate p53-regulated, mitochondrial turnover responses prevail to protect the genome and ultimately facilitate a shift from aerobic glycolysis to oxidative phosphorylation, adaptations critical for endurance-based exercise that are commensurate with p53's role as a tumour suppressor. Despite these observations, several discrepancies exist between rodent and human studies pinpointing p53 subcellular trafficking from nuclear-to-mitochondrial compartments following acute exercise. Such interspecies differences in p53 activity and the plausible p53-mediated adaptations to chronic exercise training will be discussed herein.
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Affiliation(s)
- W. J. Smiles
- Mary MacKillop Institute for Health Research; Centre for Exercise and Nutrition; Australian Catholic University; Melbourne Vic. Australia
| | - D. M. Camera
- Mary MacKillop Institute for Health Research; Centre for Exercise and Nutrition; Australian Catholic University; Melbourne Vic. Australia
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9
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Klein BJ, Wang X, Cui G, Yuan C, Botuyan MV, Lin K, Lu Y, Wang X, Zhao Y, Bruns CJ, Mer G, Shi X, Kutateladze TG. PHF20 Readers Link Methylation of Histone H3K4 and p53 with H4K16 Acetylation. Cell Rep 2017; 17:1158-1170. [PMID: 27760318 DOI: 10.1016/j.celrep.2016.09.056] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 09/05/2016] [Accepted: 09/16/2016] [Indexed: 01/06/2023] Open
Abstract
PHF20 is a core component of the lysine acetyltransferase complex MOF (male absent on the first)-NSL (non-specific lethal) that generates the major epigenetic mark H4K16ac and is necessary for transcriptional regulation and DNA repair. The role of PHF20 in the complex remains elusive. Here, we report on functional coupling between methylation readers in PHF20. We show that the plant homeodomain (PHD) finger of PHF20 recognizes dimethylated lysine 4 of histone H3 (H3K4me2) and represents an example of a native reader that selects for this modification. Biochemical and structural analyses help to explain this selectivity and the preference of Tudor2, another reader in PHF20, for dimethylated p53. Binding of the PHD finger to H3K4me2 is required for histone acetylation, accumulation of PHF20 at target genes, and transcriptional activation. Together, our findings establish a unique PHF20-mediated link between MOF histone acetyltransferase (HAT), p53, and H3K4me2, and suggest a model for rapid spreading of H4K16ac-enriched open chromatin.
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Affiliation(s)
- Brianna J Klein
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Xiaoyan Wang
- Department of Epigenetics and Molecular Carcinogenesis, Center for Cancer Epigenetics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; Faculty of Medicine, Ludwig Maximilian University of Munich, Munich 80336, Germany
| | - Gaofeng Cui
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
| | - Chao Yuan
- Department of Epigenetics and Molecular Carcinogenesis, Center for Cancer Epigenetics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | | | - Kevin Lin
- Department of Epigenetics and Molecular Carcinogenesis, Center for Cancer Epigenetics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Yue Lu
- Department of Epigenetics and Molecular Carcinogenesis, Center for Cancer Epigenetics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Xiaolu Wang
- Department of Epigenetics and Molecular Carcinogenesis, Center for Cancer Epigenetics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Yue Zhao
- Department of General, Visceral and Tumor Surgery, University Clinic Cologne, Cologne 50931, Germany
| | - Christiane J Bruns
- Faculty of Medicine, Ludwig Maximilian University of Munich, Munich 80336, Germany; Department of General, Visceral and Tumor Surgery, University Clinic Cologne, Cologne 50931, Germany
| | - Georges Mer
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA.
| | - Xiaobing Shi
- Department of Epigenetics and Molecular Carcinogenesis, Center for Cancer Epigenetics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| | - Tatiana G Kutateladze
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO 80045, USA.
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Granata C, Oliveira RSF, Little JP, Renner K, Bishop DJ. Sprint-interval but not continuous exercise increases PGC-1α protein content and p53 phosphorylation in nuclear fractions of human skeletal muscle. Sci Rep 2017; 7:44227. [PMID: 28281651 PMCID: PMC5345041 DOI: 10.1038/srep44227] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Accepted: 02/06/2017] [Indexed: 12/18/2022] Open
Abstract
Sprint interval training has been reported to induce similar or greater mitochondrial adaptations to continuous training. However, there is limited knowledge about the effects of different exercise types on the early molecular events regulating mitochondrial biogenesis. Therefore, we compared the effects of continuous and sprint interval exercise on key regulatory proteins linked to mitochondrial biogenesis in subcellular fractions of human skeletal muscle. Nineteen men, performed either 24 min of moderate-intensity continuous cycling at 63% of WPeak (CE), or 4 × 30-s “all-out” cycling sprints (SIE). Muscle samples (vastus lateralis) were collected pre-, immediately (+0 h) and 3 (+3 h) hours post-exercise. Nuclear p53 and PHF20 protein content increased at +0 h, with no difference between groups. Nuclear p53 phosphorylation and PGC-1α protein content increased at +0 h after SIE, but not CE. We demonstrate an exercise-induced increase in nuclear p53 protein content, an event that may relate to greater p53 stability - as also suggested by increased PHF20 protein content. Increased nuclear p53 phosphorylation and PGC-1α protein content immediately following SIE but not CE suggests these may represent important early molecular events in the exercise-induced response to exercise, and that SIE is a time-efficient and possibly superior option than CE to promote these adaptations.
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Affiliation(s)
- Cesare Granata
- Institute of Sport, Exercise and Active Living (ISEAL), College of Sport and Exercise Science, Victoria University, Melbourne, Australia
| | - Rodrigo S F Oliveira
- Institute of Sport, Exercise and Active Living (ISEAL), College of Sport and Exercise Science, Victoria University, Melbourne, Australia
| | - Jonathan P Little
- School of Health and Exercise Sciences, University of British Columbia Okanagan, Kelowna, British Columbia, Canada
| | - Kathrin Renner
- Department of Internal Medicine III, University Hospital of Regensburg, Regensburg, Germany
| | - David J Bishop
- Institute of Sport, Exercise and Active Living (ISEAL), College of Sport and Exercise Science, Victoria University, Melbourne, Australia
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Mendham AE, Duffield R, Coutts AJ, Marino FE, Boyko A, McAinch AJ, Bishop DJ. Similar mitochondrial signaling responses to a single bout of continuous or small-sided-games-based exercise in sedentary men. J Appl Physiol (1985) 2016; 121:1326-1334. [DOI: 10.1152/japplphysiol.00289.2016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 10/03/2016] [Accepted: 10/09/2016] [Indexed: 12/14/2022] Open
Abstract
This study assessed the mitochondrial related signaling responses to a single bout of noncontact, modified football (touch rugby), played as small-sided games (SSG), or cycling (CYC) exercise in sedentary, obese, middle-aged men. In a randomized, crossover design, nine middle-aged, sedentary, obese men completed two, 40-min exercise conditions (CYC and SSG) separated by a 21-day recovery period. Heart rate (HR) and ratings of perceived exertion (RPE) were collected during each bout. Needle biopsies from the vastus lateralis muscle were collected at rest and 30 and 240 min postexercise for analysis of protein content and phosphorylation (PGC-1α, SIRT1, p53, p53Ser15, AMPK, AMPKThr172, CAMKII, CAMKIIThr286, p38MAPK, and p38MAPKThr180/Tyr182) and mRNA expression (PGC-1α, p53, NRF1, NRF2, Tfam, and cytochrome c). A main effect of time effect for both conditions was evident for HR, RPE, and blood lactate ( P < 0.05), with no condition by time interaction ( P > 0.05). Both conditions increased PGC1-α protein and mRNA expression at 240 min ( P < 0.05). AMPKThr172 increased 30 min post CYC ( P < 0.05), with no change in SSG ( P > 0.05). CYC increased p53 protein content at 240 min to a greater extent than SSG ( P < 0.05). mRNA expression of NRF2 decreased in both conditions ( P < 0.05). No condition by time interactions were evident for mRNA expression of Tfam, NRF1, cytochrome c, and p53. The similar PGC-1α response between intensity-matched conditions suggests both conditions are of similar benefit for stimulating mitochondrial biogenesis. Differences between conditions regarding fluctuation in exercise intensity and type of muscle contraction may explain the increase of p53 and AMPK within CYC and not SSG (noncontact, modified football).
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Affiliation(s)
- Amy E. Mendham
- Division of Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town, Cape Town, South Africa
- School of Exercise Science, Sport and Health, Charles Sturt University, Bathurst, New South Wales, Australia
| | - Rob Duffield
- Sport and Exercise Discipline Group, UTS: Health, University of Technology Sydney (UTS), Moore Park, New South Wales, Australia
| | - Aaron J. Coutts
- Sport and Exercise Discipline Group, UTS: Health, University of Technology Sydney (UTS), Moore Park, New South Wales, Australia
| | - Frank E. Marino
- School of Exercise Science, Sport and Health, Charles Sturt University, Bathurst, New South Wales, Australia
| | - Andriy Boyko
- Sport and Exercise Discipline Group, UTS: Health, University of Technology Sydney (UTS), Moore Park, New South Wales, Australia
| | - Andrew J. McAinch
- Centre for Chronic Diseases, College of Health and Biomedicine, Victoria University, Melbourne, Victoria, Australia
- Institute of Sport, Exercise and Active Living (ISEAL), Victoria University, Melbourne, Victoria, Australia; and
| | - David John Bishop
- Institute of Sport, Exercise and Active Living (ISEAL), Victoria University, Melbourne, Victoria, Australia; and
- School of Medical and Health Sciences, Edith Cowan University, Joondalup, Western Australia, Australia
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12
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Granata C, Oliveira RSF, Little JP, Renner K, Bishop DJ. Training intensity modulates changes in PGC-1α and p53 protein content and mitochondrial respiration, but not markers of mitochondrial content in human skeletal muscle. FASEB J 2015; 30:959-70. [PMID: 26572168 DOI: 10.1096/fj.15-276907] [Citation(s) in RCA: 136] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Accepted: 10/28/2015] [Indexed: 12/28/2022]
Abstract
Exercise training has been associated with increased mitochondrial content and respiration. However, no study to date has compared in parallel how training at different intensities affects mitochondrial respiration and markers of mitochondrial biogenesis. Twenty-nine healthy men performed 4 wk (12 cycling sessions) of either sprint interval training [SIT; 4-10 × 30-s all-out bouts at ∼200% of peak power output (WPeak)], high-intensity interval training (HIIT; 4-7 × 4-min intervals at ∼90% WPeak), or sublactate threshold continuous training (STCT; 20-36 min at ∼65% WPeak). The STCT and HIIT groups were matched for total work. Resting biopsy samples (vastus lateralis) were obtained before and after training. The maximal mitochondrial respiration in permeabilized muscle fibers increased significantly only after SIT (25%). Similarly, the protein content of peroxisome proliferator-activated receptor γ coactivator (PGC)-1α, p53, and plant homeodomain finger-containing protein 20 (PHF20) increased only after SIT (60-90%). Conversely, citrate synthase activity, and the protein content of TFAM and subunits of the electron transport system complexes remained unchanged throughout. Our findings suggest that training intensity is an important factor that regulates training-induced changes in mitochondrial respiration and that there is an apparent dissociation between training-induced changes in mitochondrial respiration and mitochondrial content. Moreover, changes in the protein content of PGC-1α, p53, and PHF20 are more strongly associated with training-induced changes in mitochondrial respiration than mitochondrial content.
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Affiliation(s)
- Cesare Granata
- *Institute of Sport, Exercise and Active Living (ISEAL), College of Sport and Exercise Science, Victoria University, Melbourne, Victoria, Australia; School of Health and Exercise Sciences, University of British Columbia Okanagan, Kelowna, British Columbia, Canada; and Department of Internal Medicine III, University Hospital of Regensburg, Regensburg, Germany
| | - Rodrigo S F Oliveira
- *Institute of Sport, Exercise and Active Living (ISEAL), College of Sport and Exercise Science, Victoria University, Melbourne, Victoria, Australia; School of Health and Exercise Sciences, University of British Columbia Okanagan, Kelowna, British Columbia, Canada; and Department of Internal Medicine III, University Hospital of Regensburg, Regensburg, Germany
| | - Jonathan P Little
- *Institute of Sport, Exercise and Active Living (ISEAL), College of Sport and Exercise Science, Victoria University, Melbourne, Victoria, Australia; School of Health and Exercise Sciences, University of British Columbia Okanagan, Kelowna, British Columbia, Canada; and Department of Internal Medicine III, University Hospital of Regensburg, Regensburg, Germany
| | - Kathrin Renner
- *Institute of Sport, Exercise and Active Living (ISEAL), College of Sport and Exercise Science, Victoria University, Melbourne, Victoria, Australia; School of Health and Exercise Sciences, University of British Columbia Okanagan, Kelowna, British Columbia, Canada; and Department of Internal Medicine III, University Hospital of Regensburg, Regensburg, Germany
| | - David J Bishop
- *Institute of Sport, Exercise and Active Living (ISEAL), College of Sport and Exercise Science, Victoria University, Melbourne, Victoria, Australia; School of Health and Exercise Sciences, University of British Columbia Okanagan, Kelowna, British Columbia, Canada; and Department of Internal Medicine III, University Hospital of Regensburg, Regensburg, Germany
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13
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Tang N, Ma L, Lin XY, Zhang Y, Yang DL, Wang EH, Qiu XS. Expression of PHF20 protein contributes to good prognosis of NSCLC and is associated with Bax expression. INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY 2015; 8:12198-12206. [PMID: 26722404 PMCID: PMC4680349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 08/26/2015] [Indexed: 06/05/2023]
Abstract
BACKGROUND Recent studies demonstrate that plant homeodomain finger protein 20 (PHF20), which was initially described as an immunogenic antigen in glioblastoma, is a putative transcriptional factor, and exhibits tumor suppressor activity. However, little is known about its expression and clinical significance in lung cancer. METHODS We investigated the expression of PHF20 in 142 cases of NSCLC tissue and 30 cases of normal lung tissue by immunohistochemical staining and downregulated PHF20 expression in SPC cell. RESULTS PHF20 expression was significantly higher in normal lung tissues than that in NSCLC tissues. The expression of PHF20 in NSCLC was significantly correlated with histological grade, p-TNM stage and lymph node metastasis. Moreover, the loss of PHF20 expression was associated with short overall survival. We also found that the expression of PHF20 was associated with Bax expression. Additionally, PHF20 markedly inhibited cell proliferation and invasion. CONCLUSIONS PHF20 may play an important role in NSCLC, and may serve as a potential therapeutic target of NSCLC.
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Affiliation(s)
- Na Tang
- Department of Pathology, The First Affiliated Hospital and College of Basic Medical Sciences, China Medical UniversityShenyang 110001, China
| | - Lin Ma
- Department of Pathology, Liaoning Tumor HospitalShenyang 110042, China
| | - Xu-Yong Lin
- Department of Pathology, The First Affiliated Hospital and College of Basic Medical Sciences, China Medical UniversityShenyang 110001, China
| | - Yong Zhang
- Department of Pathology, The First Affiliated Hospital and College of Basic Medical Sciences, China Medical UniversityShenyang 110001, China
| | - Da-Lei Yang
- Center for Assisted Reproduction, Department of Obstetrics and Gynecology, Shengjing Hospital, China Medical UniversityShenyang 110004, China
| | - En-Hua Wang
- Department of Pathology, The First Affiliated Hospital and College of Basic Medical Sciences, China Medical UniversityShenyang 110001, China
| | - Xue-Shan Qiu
- Department of Pathology, The First Affiliated Hospital and College of Basic Medical Sciences, China Medical UniversityShenyang 110001, China
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14
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Autophagy is upregulated in ovarian endometriosis: a possible interplay with p53 and heme oxygenase-1. Fertil Steril 2015; 103:1244-51.e1. [DOI: 10.1016/j.fertnstert.2015.02.007] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Revised: 01/27/2015] [Accepted: 02/05/2015] [Indexed: 12/31/2022]
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15
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Chen CS, Ho DR, Chen FY, Chen CR, Ke YD, Su JGJ. AKT mediates actinomycin D-induced p53 expression. Oncotarget 2015; 5:693-703. [PMID: 24525337 PMCID: PMC3996664 DOI: 10.18632/oncotarget.1328] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
At high cytotoxic concentrations, actinomycin D (ActD) blocks transcription, decreasing levels of MDM2 and thus causing p53 stabilization. At low cytostatic concentrations, ActD causes ribosomal stress, which decreases MDM2 activity, resulting in p53 stabilization and activation. ActD can thus be used for p53-based cyclotherapy. We analyzed pathways mediating ActD-induced p53 expression. Inhibitors (LY294002, wortmannin, and deguelin) of phosphatidylinositol 3-kinases (PI3K) and AKT, but not inhibitors of MEK1/2, JNK, and p38-MAPK abolished the ActD-induced p53 expression in diverse cell types. RNA interference further supported these results. When AKT was downregulated by small hairpin RNA-AKTs, ActD-induced p53 expression was significantly decreased. ActD caused AKT phosphorylation at Ser473, indicating full activation of AKT. The potential for cancer therapy is discussed.
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Affiliation(s)
- Chih-Shou Chen
- Division of Urology, Department of Surgery, Chang Gung Memorial Hospital, Chiayi, Taiwan, ROC
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16
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Lasho TL, Pardanani A, Tefferi A, Smith DI. Altered expression of tumor suppressor PHF20 in myeloproliferative neoplasms. Leukemia 2014; 28:1762-4. [PMID: 24675105 DOI: 10.1038/leu.2014.117] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- T L Lasho
- Mayo College of Medicine, Mayo Clinic, Rochester, MN, USA
| | - A Pardanani
- Division of Hematology, Department of Internal Medicine, Mayo Clinic, Rochester, MN, USA
| | - A Tefferi
- Division of Hematology, Department of Internal Medicine, Mayo Clinic, Rochester, MN, USA
| | - D I Smith
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
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17
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Nguyen TA, Menendez D, Resnick MA, Anderson CW. Mutant TP53 posttranslational modifications: challenges and opportunities. Hum Mutat 2014; 35:738-55. [PMID: 24395704 DOI: 10.1002/humu.22506] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Accepted: 01/02/2014] [Indexed: 12/13/2022]
Abstract
The wild-type (WT) human p53 (TP53) tumor suppressor can be posttranslationally modified at over 60 of its 393 residues. These modifications contribute to changes in TP53 stability and in its activity as a transcription factor in response to a wide variety of intrinsic and extrinsic stresses in part through regulation of protein-protein and protein-DNA interactions. The TP53 gene frequently is mutated in cancers, and in contrast to most other tumor suppressors, the mutations are mostly missense often resulting in the accumulation of mutant (MUT) protein, which may have novel or altered functions. Most MUT TP53s can be posttranslationally modified at the same residues as in WT TP53. Strikingly, however, codons for modified residues are rarely mutated in human tumors, suggesting that TP53 modifications are not essential for tumor suppression activity. Nevertheless, these modifications might alter MUT TP53 activity and contribute to a gain-of-function leading to increased metastasis and tumor progression. Furthermore, many of the signal transduction pathways that result in TP53 modifications are altered or disrupted in cancers. Understanding the signaling pathways that result in TP53 modification and the functions of these modifications in both WT TP53 and its many MUT forms may contribute to more effective cancer therapies.
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Affiliation(s)
- Thuy-Ai Nguyen
- Chromosome Stability Section, Laboratory of Molecular Genetics, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina
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18
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Zhang T, Park KA, Li Y, Byun HS, Jeon J, Lee Y, Hong JH, Kim JM, Huang SM, Choi SW, Kim SH, Sohn KC, Ro H, Lee JH, Lu T, Stark GR, Shen HM, Liu ZG, Park J, Hur GM. PHF20 regulates NF-κB signalling by disrupting recruitment of PP2A to p65. Nat Commun 2013; 4:2062. [PMID: 23797602 DOI: 10.1038/ncomms3062] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Accepted: 05/28/2013] [Indexed: 01/01/2023] Open
Abstract
Constitutive NF-κB activation in cancer cells is caused by defects in the signalling network responsible for terminating the NF-κB response. Here we report that plant homeodomain finger protein 20 (PHF20) maintains NF-κB in an active state in the nucleus by inhibiting the interaction between PP2A and p65. We show that PHF20 induces canonical NF-κB signalling by increasing the DNA-binding activity of NF-κB subunit p65. In PHF20 overexpressing cells, the termination of tumour necrosis factor-induced p65 phosphorylation is impaired whereas upstream signalling events triggered by tumour necrosis factor are unaffected. This effect strictly depends on the interaction between PHF20 and methylated lysine residues of p65, which hinders recruitment of PP2A to p65, thereby maintaining p65 in a phosphorylated state. We further show that PHF20 levels correlate with p65 phosphorylation levels in human glioma specimens. Our work identifies PHF20 as a novel regulator of NF-κB activation and suggests that elevated expression of PHF20 may drive constitutive NF-κB activation in some cancers.
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Affiliation(s)
- Tiejun Zhang
- Department of Pharmacology, Infection Signaling Network Research Center, College of Medicine, Chungnam National University, Daejeon 301 747, South Korea
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19
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Emerging roles for chromatin as a signal integration and storage platform. Nat Rev Mol Cell Biol 2013; 14:211-24. [PMID: 23524488 DOI: 10.1038/nrm3545] [Citation(s) in RCA: 210] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Cells of a multicellular organism, all containing nearly identical genetic information, respond to differentiation cues in variable ways. In addition, cells are plastic, able to execute their specialized function while maintaining the ability to adapt to environmental changes. This is achieved through multiple mechanisms, including the direct regulation of chromatin-based processes in response to stimuli. How signal transduction pathways directly communicate with chromatin to change the epigenetic landscape is poorly understood. The preponderance of covalent modifications on histone tails coupled with a relatively small number of functional outputs raises the possibility that chromatin acts as a site of signal integration and storage.
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20
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Zhao W, Li Q, Ayers S, Gu Y, Shi Z, Zhu Q, Chen Y, Wang HY, Wang RF. Jmjd3 inhibits reprogramming by upregulating expression of INK4a/Arf and targeting PHF20 for ubiquitination. Cell 2013; 152:1037-50. [PMID: 23452852 DOI: 10.1016/j.cell.2013.02.006] [Citation(s) in RCA: 123] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Revised: 11/20/2012] [Accepted: 02/05/2013] [Indexed: 02/02/2023]
Abstract
Although somatic cell reprogramming to generate inducible pluripotent stem cells (iPSCs) is associated with profound epigenetic changes, the roles and mechanisms of epigenetic factors in this process remain poorly understood. Here, we identify Jmjd3 as a potent negative regulator of reprogramming. Jmjd3-deficient MEFs produced significantly more iPSC colonies than did wild-type cells, whereas ectopic expression of Jmjd3 markedly inhibited reprogramming. We show that the inhibitory effects of Jmjd3 are produced through both histone demethylase-dependent and -independent pathways. The latter pathway involves Jmjd3 targeting of PHF20 for ubiquitination and degradation via recruitment of an E3 ligase, Trim26. Importantly, PHF20-deficient MEFs could not be converted to fully reprogrammed iPSCs, even with knockdown of Jmjd3, Ink4a, or p21, indicating that PHF20 is required for reprogramming. Our findings demonstrate, to the best of our knowledge, a previously unrecognized role of Jmjd3 in cellular reprogramming and provide molecular insight into the mechanisms by which the Jmjd3-PHF20 axis controls this process.
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Affiliation(s)
- Wei Zhao
- Center for Inflammation and Epigenetics, The Methodist Hospital Research Institute, Houston, TX 77030, USA
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21
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Cheung M, Testa JR. Diverse mechanisms of AKT pathway activation in human malignancy. Curr Cancer Drug Targets 2013; 13:234-44. [PMID: 23297823 DOI: 10.2174/1568009611313030002] [Citation(s) in RCA: 128] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Revised: 07/20/2012] [Accepted: 01/08/2013] [Indexed: 01/12/2023]
Abstract
AKT/PKB (Protein Kinase B) are central proteins mediating signals from receptor tyrosine kinases and phosphatidylinositol 3-kinase. AKT kinases are involved in a number of important cellular processes including cell proliferation and survival, cell size in response to nutrient availability, tumor invasion/metastasis, and angiogenesis.Various components of the AKT signaling pathway are encoded by tumor suppressor genes and oncogenes whose loss or activation, respectively, plays an important role in tumorigenesis. The growing body of evidence connecting deregulated AKT signaling with sporadic human cancers and inherited cancer predisposition syndromes is discussed. We also highlight new findings regarding the involvement of activating mutations of AKT1, AKT2, and AKT3 in somatic overgrowth disorders: Proteus syndrome, hypoglycemia with hypertrophy, and hemimegalencephaly, respectively. In addition, we review recent literature documenting the various ways the AKT signaling pathway is activated in human cancers and consequences for molecularly targeted therapies.
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Affiliation(s)
- Mitchell Cheung
- Cancer Biology Program, Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111-2497, USA
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22
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PHF20 is an effector protein of p53 double lysine methylation that stabilizes and activates p53. Nat Struct Mol Biol 2012; 19:916-24. [PMID: 22864287 DOI: 10.1038/nsmb.2353] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2011] [Accepted: 07/06/2012] [Indexed: 12/26/2022]
Abstract
PHF20 is a multidomain protein and subunit of a lysine acetyltransferase complex that acetylates histone H4 and p53 but whose function is unclear. Using biochemical, biophysical and cellular approaches, we determined that PHF20 is a direct regulator of p53. A Tudor domain in PHF20 recognized p53 dimethylated at Lys370 or Lys382 and a homodimeric form of this Tudor domain could associate with the two dimethylated sites on p53 with enhanced affinity, indicating a multivalent interaction. Association with PHF20 promotes stabilization and activation of p53 by diminishing Mdm2-mediated p53 ubiquitylation and degradation. PHF20 contributes to upregulation of p53 in response to DNA damage, and ectopic expression of PHF20 in different cell lines leads to phenotypic changes that are hallmarks of p53 activation. Overall our work establishes that PHF20 functions as an effector of p53 methylation that stabilizes and activates p53.
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